Continuous unwinding apparatus for web material

ABSTRACT

Continuous unwinding apparatus for web material comprises a pair of opposed end stands, each of which carries a pair of rollcarrying arms mounted for independent rotation on a common axis, and a splicer assembly is mounted for adjusting movement with respect to the end stands to accommodate rolls of definite diameters. There is no center shaft between the end stands, but separate drives couple opposed pairs of arms and provide for driving each coupled pair in either direction in any desired speed. An outstanding characteristic of the apparatus is that the movements of each pair of arms between splicing and final unwinding positions are confined to two quadrants of rotation.

nited States Patent [19] Q Phelps et a]. I

m] 3,831,876 Aug. 27, 1974 CONTINUOUS UNWINDING APPARATUS FOR WEBMATERIAL Tetro, both of Fulton, N.Y.

Assignee: The Black Clawson Company,

Middletown, Ohio Dec. 11, 1972 U.S. Cl 242/583, 242/56 Int. Cl. B65h19/14 Field of Search 242/583, 58.2, 58.4, 56

- References Cited UNITED STATES- PATENTS 2/1969 9/1963 6/ 1967 6/ 1967Huck Huck Blessing Anderson 242/583 T Primary ExaminerJohn W. HuckertAssistant ExaminerEdward J. McCarthy Attorney, Agent, or FirmBiebel,French & Bugg ABSTRACT Continuous unwinding apparatus for web materialcomprises a pair of opposed end stands, each of which carries a pair ofroll-carrying arms mounted for independent rotation on a common axis,and a splicer assembly is mounted for adjusting movement with respect tothe end stands to accommodate rolls of definite diameters. There is nocenter shaft between the end stands, but separate drives couple opposedpairs of arms and provide for driving each coupled pair in eitherdirection in any desired speed. An outstanding characteristic of theapparatus is that the movements of each pair of arms between splicingand final unwinding positions are confined to two quadrants of rotation.

9 Claims, 14 Drawing Figures I I l I 'r1' 8' r1 4: 1 T 5 :1. II I I L?Li, is 15% 45" ..34 124 I M *1 /Z' I W- BACKGROUND OF THE INVENTION Inany process line for using or otherwise operating on paper or othercontinuous web material, there is at least one fixed station where pullrolls or other web drive means cause the web to travel from an up streamsource to a downstream work station. Commonly the tension of the web iscontinuously measured between its source and the drive means to providea control factor for the speed of the drive means.

It has been common for many years to utilize, as the supply source forsuch a line, unwinding apparatus which comprises a reel having two ormore arms at opposite ends of a main shaft. In use, each opposed pair ofreel arms successively receives a roll of web material to be unwound,and the reel is indexed to advance each pair of arms from a stationwhere the expiring roll is unloaded and replaced with a full roll to amain unwinding station adjacent the next station in the process line.Continuous unwinding is provided by a splicing mechanism at or near themain unwinding station for severing the web from an expired roll andsplicing the resulting web tail to the leading end of the web on a newroll.

Such reels are generally satisfactory for handling paper and other webmaterial of relatively low elasticity and resistance to stretching. Theyhave definite disadvantages, however, for handling web material, such asplastic, having significant plastic memory, and they are particularlyunsatisfactory for handling relatively limp plastics which are easilystretched but have low ability to recover from stretching.

A major reason for these disadvantages is best explained in connectionwith a two-arm continuous unwinder. Since the arms are 180 removed fromeach other on the reel, the unwinding and reloading positions for eachroll are similarly on opposite sides of the reel. Each successiveexpiring roll must therefore move through a substantial angular portion,approaching 180, of rotation of the roll from its main unwindingposition in preparation for splicing.

During such movement, there is a considerable increase on the length ofdraw of the web from the expiring roll, and also the tension of thatportion of the web tends to increase if the surface speed of the rollremains relatively constant. Further, since the expiring roll and thenew roll are in relatively fixed position in the reel, each must takepart in all indexing movement for the other, including the finalindexing movement of the new roll as it is spliced to the web from theexpiring roll. The ultimate result of these movement, coupled with theefforts of the tension control mechanism to correct for them, canseriously affect the operations of the rest of the process line and theproduct produced thereon.

An additional complication resulting from the conditions outlined aboveis related to the variation in length of the portion of web between eachexpiring roll and the nearest supporting or guide roll in the line. Ifthe web is paper of adequate strength and resistance to streching, itmay be able to support itself satisfactorily, but serious problems ofsagging and localized stretching can occur if the web material is a limpplastic. In addition, such local sagging can further complicate theefforts of the tension control means to maintain constant tensionconditions along the process line.

SY OF THE INVENTION The present invention has as its primary objectivethe provision of continuous unwinding apparatus which will be free ofthe above outlined disadvantages. It accomplishes this objective by areel construction comprising a pair of opposed end stands each of whichcarries two roll supporting arms mounted for rotation on a common axisthrough 360 in both directions. These arms are coupled in opposed pairsby individually operable drive means such that each coupled pair can berotated at any selected speed with respect to and independently of theother pair.

This construction of the reel and its drive means make it possible tocarry on all of the essential functions of loading, splicing, unwindingand unloading in only two of the four quadrants of rotation of thepaired reel arms, with the other two quadrants being used only forrotation of each successive unloaded pair of arms to loading position.The invention also makes available each and all of the followingpractical advantages over conventional continuous unwinding apparatus:

a. Decreased change in the web path during indexing.

b. Decreased change in the length of draw of the web during splicing.

c. Decreased requirements of indexing speed for completion of eachcycle, which in turn contributes to accurately timed acceleration anddeceleration of the rolls.

d. No indexing movement of the expiring rell during indexing of the fullroll to splicing position.

e. Easy adjustment for accommodation of rolls of different sizes.

f. Easy change to present either the inner or the outer surface of theweb uppermost in the process line.

In the preferred construction in accordance with the invention, each ofthe end stands assemblies is a duplicate of the other but is physicallyseparate therefrom except for the drawing connections betweencorresponding components parts. There is no common shaft on the axis ofthe opposed reel arms, so that the center and one side of the apparatusis essentially open at all times, and this side is directed toward theassociated process line. The splicing mechanism is mounted for movementbetween the reel and the rest of the process line so that it can enterthe open space between the end stands and thereby position the pressureand guide rolls which are component parts thereof in close proximity tothe successive rolls from which they receive the web. Similan'ly, thesplicing mechanism can be adjusted toward and away from the reel asrequired for optimum results with rolls of different diameters.

These and other advantages, and the means by which they are achieved,will be apparent from the detailed description which follows inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a plan view of continuousunwinding apparatus in accordance with the invention, with no rollcarried by either pair of arms;

FIG. 2 is an elevation of the apparatus of FIG. 1 looking from left toright in FIG. 3;

FIG. 3 is an elevation looking from right to left in FIG. 2 and showingthe apparatus with one roll unwinding and a full roll ready to beunwound;

FIG. 4 is an enlarged fragmentary section on the line 4-4 of FIG. 1;

FIG. 5 is an enlarged fragmentary section on the line 5-5 of FIG. 1',

FIG. 6 is a view looking in the same direction as FIG. 3 and showing thesplicer assembly in two relatively moved positions;

FIGS. 7-11) are semi-diagrammatic views illustrating successive stagesof unwinding and under splicing with the apparatus of FIGS. 1-6; and

FIGS. 11-14 are views similar to FIGS. 7-10 illustrating successivestages of unwinding and over splicing with the apparatus of FIGS. 1-6.

DESCRIPTION OF THE PREFERRED EMBODIMENT The unwinding apparatus shown inthe drawings comprises two essential identical end stand and drivingassemblies mounted at opposite ends of a common base 10. The assembly atthe right-hand end of FIGS. 1 and 2 comprises a gear case 11 in whichare mounted two roll supporting arms 12 and 13 of the same radialdimensions. The arm 12 is straight, but arm 13 axially offset so thatits radially outer end portion is aligned with arm 12, and the two armsare mounted for independent rotation in either direction. As shown inFIG. 4, arm 12 has a straight supporting shaft 15 provided with a wormgear 16 at its outer end, and arm 13 is carried by a hollow shaft 17which surrounds shaft 15 and carries a similar worm gear 18.

The end stand assembly at the opposite end of base comprises a gear case21 of the same construction as gear case 11 in which are mounted twoarms 12 and 13' identical with the arms 12 and 13 respectively andsimilarly mounted for rotation on the same axis 22 as arms 12-13. Thestraight arm 12 is carried by a straight hollow shaft 25 having a wormgear 26 at its outer end, and the offset arm 13 is carried by a hollowshaft 27 concentric with and partially enclosing shaft 25 and alsoprovided with a worm gear 28. Opposed pairs of dissimilar arms arecoupled by driving connections causing each pair to operate as a unit.

The drive for the paired arms 12 and 13' comprises 'a motor 30 inhousing 31 which drives arm shaft through a transmission 32, universalconnection 33 and worm 34. The shaft 35 extends from transmission 32 toa similar transmission 36 in housing 37 from which it is transmittedthrough the universal connection 38 to a worm 39 driving gear 28.Similarly the drive for arms 12 and 13 comprises a motor (not shown) inhousing 37 which drives arm shaft through a transmission 42, universalconnection 43 and worm 44 driving gear 26. The same drive is transmittedthrough the shaft 45 to a transmission 46 in housing 31 and then in turnthrough the universal connection 48 to a worm 49 driving gear 18.

Each of arms 12-13 and 12'-13 is provided with a spindle for holding oneend of a shaft or core supporting a roll to be unwound, and each pair ofspindles is provided with a drive for controlling its rotational speedto maintain proper tension in the unwinding web. Referring to FIG. 4,the arm 12 carries a spindle 511 keyed at 51 in a sleeve 52 rotatable inthe outer end of the arm. The drive motor 55 for spindle 511 is mountedon the housing 31 beside end stand 11 and is connected through a beltdrive 54 with the drive spindle 56 which extends through the shaft 15supporting arm 12. -A drive sprocket 57 on the inner end of spindle 56drives sprocket 58 on sleeve 52 through a suitable drive chain 59.

The spindle 59 is also mounted for axial movement in arm 12 for loadingand unloading purposes. As shown in FIG. 5, spindle 511 is axiallymovable in the sleeve 52, and this movement is effected by an air motor611 connected through gears 61-62 to a lead screw 63 operating a thrustnut 65. A collar 66 connects the ends of nut 65 and spindle 511 so thataxial movement of the nut in response to rotation of lead screw 63causes corresponding axial movement of spindle 511. The drives forspindle 511 are duplicated for the corresponding spindle 50 in arm 12'as indicated by the motor 55 on housing 37.

The core spindle 70 in arm 13 which is paired with spindle 50 is alignedwith spindle 511 and accordingly needs no drive control, but it isprovided with an axial drive for loading and unloading purposes.Referring to FIG. 5, an air motor 72 has a driving connection throughgears 73-74 to lead screw 75, and the thrust nut 76 driven by lead screwis connected by collar 77 with the other end of spindle 70. Thisconstruction is duplicated for the spindle 70' in arm 13'.

As best seen in FIG. 1, the construction and arrangement of the endstand and drive assemblies makes it possible to leave one side of theapparatus essentially open, and the splicer assembly is mounted foradjusting movement in this space. Referring to FIGS. 1-3 and 6, thesplicer assembly comprises a pair of complementary end frames 91) and 91mounted for sliding movement on base 10 with the aid of gibs and guidesindicated generally at 92. As described hereinafter, the movement of theframe -91 is for the purpose of adjustment to handle rolls of differentsizes, and it is effected and controlled by a drive motor 95 operating apair of screw jacks 96 through a cross shaft 97.

The main operating components of the splicer assembly comprise the knife1011, two paster rolls 1111-102, and two guide rolls 1113 and 1114. Thepaster rolls are used alternatively depending on whether the inside oroutside of the web being unwound is to be presented uppermost to theprocess line. Each paster roll is mounted at each end by a lever pivotedat 1116 on the associated frame 911 or 91 and biased against swingingmovement in one direction by an air cylinder 1117 or other suitablebiasing means.

The knife 11111 is carried by a rack shaft mounted in the frames 911-91and provided at each end with a pinion 111 meshing with a rack 112mounted for longitudinal reciprocation in the frame by an air cylinder115 assembly which is selectively operable in either direction andincludes shock absorbing springs 116. Knife 11111 is selectivelyoperated in either direction depending upon whether the process linecalls for over splicing (the inside of the web uppermost) or undersplicing (the outside of the web uppermost). It is shown as arranged forunder splicing, with the rack 112 fully advanced so that firing ofcylinder 115 will cause the rack to retract and the knife to swingcounterclockwise.

FIGS. 3 and 7-1@ show the operating sequence for under splicing. In FIG.3, the roll 12% is supported in its final unwinding position by arm 12and its complementary arm 13, with the web wrapping the underside ofpaster roll 102 and the upper side of guide roll 103, and the new roll121 has already been loaded in arms 13 and 12. Unwinding continueswithout requiring movement of either pair of arms from the positionsshown in FIG. 3, but during this interval, roll 121 should be preparedfor splicing, as by the application of adhesive or other conventionalprocedure.

When roll 120 is almost completely unwound, the drive to spindle 50' isactuated to bring the surface speed of roll 121 up to that of the webunwinding from roll 120, and arms 12'-13 are indexed counterclockwiseuntil the surface of roll 121 is pressed against the web wrapping pasterroll 102, as shown in FIG. 7. At the same instant, cylinders 115 arefired to drive knife 100 through its cutting cycle wherein it severs theweb between roll 120 and paster roll 102, as shown in FIG. 7. If thesize of the core and the geometry of the system requires that arms 12-13move past 12:00 clock to assure that the expiring web is adequatelywithin the stroke of the knife, the arms are indexed accordingly as apart of the splicing sequence. Immediately following splicing, the arms12'-13 are indexed clockwise sufficiently to establish clearance betweenthe surface of roll 121 and paster roll 102 as unwinding continues fromroll 121 in the position of the parts shown in FIG. 8.

As soon as roll 121 begins to unwind, the expired roll and supportingcore are removed from 12-13, which may be done with those arms at anyconvenient position in the angular range shown in FIG. 9. Both pairs ofarms can then be rotated clock-wise to the reverse of their positionsshown in FIG. 3, but arms 12-13 carrying the unwinding roll 121 requiremovement of considerably less than 180, while the empty arms 12-13' willmove closer to 240. A new roll can then be loaded in arms 12-13', toreestablish the conditions shown in FIG. 3, as soon as roll 121 hasunwound sufficiently to provide space for the new roll, for example to adiameter of 24 inches if its initial diameter was 40 inches, and forsmaller rolls, reloading can be done substantially immediately.

It is apparent from the description of the operating sequence and FIGS.3 and 7-10 that the essential operations of loading, unwinding, splicingand reloading take place in less than 180 of the total rotationalmovement of each pair of arms, and essentially in the two quadrants ofarm rotation which lie on the opposite side of the common axis 22 of thearms from the splicer assembly and the direction in which the webtravels from the apparatus. In fact, the total movement of each pair ofarms from splicing position to severing position is substantially lessthan 180 and need not exceed approximately 150 even for rolls of themaximum diameter which the apparatus is designed to handle.

Two important advantages result from this twoquadrant feature. One isthat the total change in the length of draw from the unwinding roll tothe paster roll 102 is relatively small, and notably less than isrequired with a conventional reel having its arms fixed on a commonshaft. For example, with the apparatus constructed as disclosed tohandle 40-inch rolls, if a partially unwound roll 120 were moved fromthe position of FIG. 11 to that of FIG. 12 without interim unwinding,the difference in the length of draw would be only about 1 foot.Further, the movement of arms 12-13 between the limit positions theyoccupy during unwinding can be at a relatively low rate such that anyvariation in the length of draw resulting from the movement does notaffect the tension in the web, and they remain stationary during themovement of arms 12-13 incident to splicing. The empty pair of arms,however, can be moved at any desired different speed without in any wayaffecting web tension or the position of the unwinding roll.

For optimum results in the use of the invention, the several drivemotors should be controlled by automatic circuit means, in accordancewith common practice in the web winding and unwinding art. No specficdisclosure of control means has therefore been included herein, since itwill be apparent to those skilled in the art ahow to control the drivesin such manner as to achieve the results described herein. how

The dotted line showings in FIG. 6 illustrate how the splicer assemblycan be adjusted to accommodate rolls 125 of the minimum diameter forwhich the apparatus is designed, e.g. 14 inches. It will be seen that inthis adjusted position, the knife 100 and paster rolls 101 and 102 lieon the same side of arm axis 22 as the arms and the unwinding rolls.FIG. 6 also shows that the arms holding a 14-inch roll in splicingposition are at an angle of only approximately 35 to the horizontal, andthey need not move beyond the corresponding angle above the horizontal,so that their total movement during unwinding will not exceedapproximately Correspondingly changed conditions are established inintermediate adjusted positions of the splicer assembly and for rolls ofintermediate diameters.

FIGS. 111-14 show the operating sequence for over splicing, wherein theinner surface of the web is presented uppermost to the process line.FIG. 11 shows the parts in the relative positions which correspond toFIG. 3, with arms 12 and 13' positioned at approximately 6 oclock tosupport 130 in its final unwinding position, with the web wrapping theuppersizde of paster roll 101 and the underside of guide roll 103, andwith a new roll 131 already loaded in arms 12-13 in approximately 10oclock position. FIG. 14 shows the parts in splicing positioncorresponding to FIG. 8, with arms 12-13 moved slightly beyond 6 oclock,and with arms 12-13 moved to approximately 11 oclock to press roll 131against the portion of the web running over paster roll 101. These viewsalso show that for over splicing, the rest position of knife is reversedfrom FIGS. 3 and t1, and its operating stroke is counterclockwise.

As described in connection with under splicing, arms 12'-13 are indexedto move roll 131 away from paster roll 101 as soon as splicing isaccomplished. FIG. 13 shows roll 131 in the resulting initial unwindingposition, and also illustrates the angular range for unloading of arms12-13. FIG. 14 corresponds to FIG. 10 and shows arms 12-13 moved to holdroll 131 in its final unwinding range of positions, and it also showsarms 12-13 ready for reloading with a full roll. It is apparent that theoperating sequence illustrated by FIGS. 11-14 offers the same advantagesof two-quadrant operation already described for under splicing, and thatthis applies to the handling of all sizes of rolls within the range forwhich the apparatus is designed and for all correspondingly adjustedpositions of the splicer assembly.

It should also be noted that although the invention has been illustratedby an embodiment wherein the two quadrants within which the operationsoccur lie on one side of a vertical reference line through the axisabout which the roll arms rotate, this is primarily because such anarrangement is convenient for many applications of the invention. itwill be readily apparent from FIGS. 7-14, however, that practice of theinvention is not limited to this particular arrangement, and that thereference line can be rotated to any other desired position, whichrequires only that the splicer assembly be correspondingly relocated.

While the method herein described, and the apparatus for carrying thismethod into effect, constitute preferred embodiments of the invention,it is to be understood that the invention is not limited to this precisemethod and apparatus, and that changes may be made in either withoutdeparting from the scope of the invention.

What is claimed is:

1. Apparatus for continously unwinding web material from successiverolls, comprising:

a. a pair of spaced opposed end stands,

b. two roll supporting arms mounted for rotation on a common axisthrough 360 in both directions in each of said end stands,

c. means coupling said arms in opposed pairs,

(1. means establishing a first unwinding position for a roll supportedby either of said pairs of arms in a first quadrant of said rotationthereof,

means establishing a final unwinding position for a roll supported byeither of said pairs of arms which lies in a second quadrant of saidrotation thereof contiguous to said first quadrant and thereforerequires less than 180 rotation of said arms from said first windingposition,

f. means establishing a splicing position for each said pair of arms insaid first quadrant wherein the web from a roll supported by one of saidpairs of arms in said final unwinding position is spliced to the end ofthe web on a new roll supported by the other said pair of arms, and

g. means for selectively driving each said coupled pair of arms ineither direction with respect to and independently of the other saidpair to provide for rotation of each said pair successively from saidfirst unwinding position to said final unwinding position atpredetermined controlled speed contemporaneously with unloading andloading of the other said pair with a new roll and rotation thereof fromsaid final unwinding position to said splicing position through theother two quadrants of said rotation of said arms.

2. Apparatus as defined in claim ll wherein both of said first andsecond quadrants lie on one side of said axis, and further comprisingguide means for conducting the web material from a roll supported ineither of said quadrants in a direction extending initially generallylaterally from said axis on the opposite side thereof from said firstand second quadrants.

3. Apparatus as defined in claim ll wherein both of said first andsecond quadrants lie on one side of said axis, and further comprisingsplicer assembly means mounted on the opposite side of said axis andincluding means for effecting severing of the web unwinding from anexpiring roll supported in said final unwinding position and means forsplicing said severed web to the end of the web on a new roll supportedin said splicing position.

4. Apparatus as defined in claim 3 wherein said splicer assembly meanscomprises,

a. a pair of paster rolls selectively engageable with the web unwindingfrom an expiring roll supported 5 in said final unwinding position topress said web into splicing contact with a new roll supported in saidsplicing position, and b. knife means selectively operable to sever suchweb at a position between said expiring and new rolls.

l 5. Apparatus as defined in claim 4 further comprising means supportingsaid splicer assembly means for movement towards and away from said axisin accordance with the diameter of each such new roll.

6. Apparatus as defined in claim 5 wherein all connections between saidend stands are located outside the projection of the circular pathstraversed by the outer ends of said arms to provide for movement of saidsplicer assembly means into the space between said end stands defined bysaid projected paths and correspondingly short travel of the web from anunwinding roll to the selected said pressure roll.

7. Apparatus as defined in claim 1 wherein both of said first and secondquadrants lie on one side of a vertical center line through said axis,and further comprising splicer assembly means mounted on the oppositeside of said center line and including means for effecting severing ofthe web unwinding from an expiring roll supported in said finalunwinding position and means for splicing said severed web to the end ofthe web on a new roll supported in said splicing position.

8. In a method of continuously unwinding web material from successiverolls in apparatus including two pairs of opposed roll supporting armsmounted independently of each other on a common axis through 360 in bothdirections, the steps comprising:

a. unwinding an initial portion of the web from a roll supported by oneof said pairs of arms in a first unwinding position located in a firstquadrant of said rotation of said arms,

b. rotating said one pair of arms at predetermined controlled speed fromsaid first winding position through less than 180 to a final unwindingposition located in a second quadrant of said rotation contiguous tosaid first quadrant while continuing said unwinding operation,

c. contemporaneously with said rotating step (b), ro-

tating said other pair of arms to said first quadrant and then loading anew roll thereon,

d. splicing the web from the resulting expired roll in said one pair ofarms to the end of the web on said new roll while retaining said otherpair of arms in said first quadrant,

e. unloading said expired roll from said one pair of arms,

f. performing said unwinding step (a) and rotating step (b) with respectto said new roll and said other 55 pair of arms,

g. rotating said unloaded pair of arms through the other two quadrantsto said first quadrant in timed relation with said rotating step (b) ofsaid other pair of arms; and

h. repeating all of said steps for successive new rolls.

side thereof from said quadrants.

# fl= 2: t

1. Apparatus for continously unwinding web material from successiverolls, comprising: a. a pair of spaced opposed end stands, b. two rollsupporting arms mounted for rotation on a common axis through 360* inboth directions in each of said end stands, c. means coupling said armsin opposed pairs, d. means establishing a first unwinding position for aroll supported by either of said pairs of arms in a first quadrant ofsaid rotation thereof, e. means establishing a final unwinding positionfor a roll supported by either of said pairs of arms which lies in asecond quadrant of said rotation thereof contiguous to said firstquadrant and therefore requires less than 180* rotation of said armsfrom said first winding position, f. means establishing a splicingposition for each said pair of arms in said first quadrant wherein theweb from a roll supported by one of said pairs of arms in said finalunwinding position is spliced to the end of the web on a new rollsupported by the other said pair of arms, and g. means for selectivelydriving each said coupled pair of arms in either direction with respectto and independently of the other said pair to provide for rotation ofeach said pair successively from said first unwinding position to saidfinal unwinding position at predetermined controlled sPeedcontemporaneously with unloading and loading of the other said pair witha new roll and rotation thereof from said final unwinding position tosaid splicing position through the other two quadrants of said rotationof said arms.
 2. Apparatus as defined in claim 1 wherein both of saidfirst and second quadrants lie on one side of said axis, and furthercomprising guide means for conducting the web material from a rollsupported in either of said quadrants in a direction extending initiallygenerally laterally from said axis on the opposite side thereof fromsaid first and second quadrants.
 3. Apparatus as defined in claim 1wherein both of said first and second quadrants lie on one side of saidaxis, and further comprising splicer assembly means mounted on theopposite side of said axis and including means for effecting severing ofthe web unwinding from an expiring roll supported in said finalunwinding position and means for splicing said severed web to the end ofthe web on a new roll supported in said splicing position.
 4. Apparatusas defined in claim 3 wherein said splicer assembly means comprises, a.a pair of paster rolls selectively engageable with the web unwindingfrom an expiring roll supported in said final unwinding position topress said web into splicing contact with a new roll supported in saidsplicing position, and b. knife means selectively operable to sever suchweb at a position between said expiring and new rolls.
 5. Apparatus asdefined in claim 4 further comprising means supporting said splicerassembly means for movement towards and away from said axis inaccordance with the diameter of each such new roll.
 6. Apparatus asdefined in claim 5 wherein all connections between said end stands arelocated outside the projection of the circular paths traversed by theouter ends of said arms to provide for movement of said splicer assemblymeans into the space between said end stands defined by said projectedpaths and correspondingly short travel of the web from an unwinding rollto the selected said pressure roll.
 7. Apparatus as defined in claim 1wherein both of said first and second quadrants lie on one side of avertical center line through said axis, and further comprising splicerassembly means mounted on the opposite side of said center line andincluding means for effecting severing of the web unwinding from anexpiring roll supported in said final unwinding position and means forsplicing said severed web to the end of the web on a new roll supportedin said splicing position.
 8. In a method of continuously unwinding webmaterial from successive rolls in apparatus including two pairs ofopposed roll supporting arms mounted independently of each other on acommon axis through 360* in both directions, the steps comprising: a.unwinding an initial portion of the web from a roll supported by one ofsaid pairs of arms in a first unwinding position located in a firstquadrant of said rotation of said arms, b. rotating said one pair ofarms at predetermined controlled speed from said first winding positionthrough less than 180* to a final unwinding position located in a secondquadrant of said rotation contiguous to said first quadrant whilecontinuing said unwinding operation, c. contemporaneously with saidrotating step (b), rotating said other pair of arms to said firstquadrant and then loading a new roll thereon, d. splicing the web fromthe resulting expired roll in said one pair of arms to the end of theweb on said new roll while retaining said other pair of arms in saidfirst quadrant, e. unloading said expired roll from said one pair ofarms, f. performing said unwinding step (a) and rotating step (b) withrespect to said new roll and said other pair of arms, g. rotating saidunloaded pair of arms through the other two quadrants to said firstquadrant in timed relation with said rotating step (b) of said otherpair of arms; and h. repeatinG all of said steps for successive newrolls.
 9. The method defined in claim 8 wherein both of said first andsecond quadrants lie on one side of a vertical center line through saidaxis, and wherein said web is guided away from said apparatus in adirection extending generally laterally of said axis on the oppositeside thereof from said quadrants.